"a datastore for tools in players backpack when players leave and load in"

-- server script 
local DataStoreService = game:GetService("DataStoreService")
local toolDataStore = DataStoreService:GetDataStore("ToolData")

game.Players.PlayerAdded:Connect(function(player)
    local playerTools = Instance.new("Folder")
    playerTools.Name = "PlayerTools"
    playerTools.Parent = player

local data
    local success, errorMessage = pcall(function()
        data = toolDataStore:GetAsync(player.UserId)
    end)

if success and data then
        for _, toolName in ipairs(data) do
            local tool = game.ServerStorage.Tools:FindFirstChild(toolName)
            if tool then
                tool:Clone().Parent = playerTools
            end
        end
    end
end)

game.Players.PlayerRemoving:Connect(function(player)
    local playerTools = player:FindFirstChild("PlayerTools")
    if playerTools then
        local data = {}
        for _, tool in ipairs(playerTools:GetChildren()) do
            table.insert(data, tool.Name)
        end

local success, errorMessage = pcall(function()
            toolDataStore:SetAsync(player.UserId, data)
        end)

if not success then
            warn("Failed to save data for player " .. player.Name .. ": " .. errorMessage)
        end
    end
end)